Andy, every cuben hybrid pack I've seen which has been beaten on a fair bit has given me cause for skepticism about the materials longevity, but I really ought to suck it up and build with it to find out for myself.

I also wonder a bit - only because my singular experience with the arc blast was on the JMT where I ran into 5 people with an arc blast; four of them had already patched their brand new packs with tape by the time I met them.

Is it the granite?

My pocketbook is happy that I'm not enamored with the Arc Blast just yet - I assume it will be fine, but I also have enough skepticism to stick with Xpac for now.

My ultralight gear I baby because I have spent too much on it not to. If I am doing off route hiking where I expect to do abrasive scrambling I wouldn't take my Arc Blast. For climbing and the like I would have taken a climbing pack that is heavier gauge material.

Cuben hybrid, is tough stuff. But in these packs, HMG included, cuben isnt used just for wt savings, 2.92 oz cuben hybrid is pretty heavy actually compared to many other fabric options. Its also mostly waterproof, for a period of time at least, and the time for waterproof taped seam packs is long overdue.

Does it wear out? maybe. But plenty have deep pockets and dont seem to mind that. Nothing lasts forever, some things just longer than others. Even if something does last forever, it will become obsolete.

I can say a few positive things about the Arc Blast. Joe is doing something right with its design. It carries weight on the hips extremely well, the simple belt is more comfortable than most, and, for some reason even with a heavy heavy bearcan, it does not try to lean away from my back at all

Dave may be referring to the frame, which is not intended to carry heavier loads. Vertically stiff but too flexible horizontally? The 50d cuben hybrid is strong stuff but not as abrasion resistant as say, 210d Cordura, and it shouldn't be given the denier and weight.

So what advantage (if any) does hybrid cuben have over Dimension Polyant fabrics?

Both have waterproof films, are reinforced with high-strength fibers, and have woven face fabrics. It looks like TX-07 is essentially the same weight as 2.92 oz/sy hybrid cuben (esp. given how little fabric goes into a pack), and less than half the price.

Regarding Cuben Hybrid vs. Dimension Polyant, I could be wrong, but I think the key differences are:

1) Cuben Hybrid uses spectra fibers bonded between the woven and waterproof (plastic) layers, which I think are superior to what DP uses (I could be totally wrong here).

2) DP fabrics are available with wider range of face fabric options

3) DP fabrics always (sometimes?) have an extra layer on the inside to protect the waterproof layer. Cuben hybrid does not.

4) DP fabrics are cheaper I think, although for a pack the actual cost difference is minor since you just need a couple yards.

So my general sense is that if you're looking for a face fabric similar to what Cuben Hybrid offers, and if you don't mind paying more, then you can get a somewhat stronger material for a similar weight of DP material. However, if you're looking for something more robust (face fabric or liner) or if you're looking for lower cost then DP is the way to go.

Both are great pack fabrics for the right application. It's great to see truly waterproof pack fabrics, not just ephemeral coatings. DP makes fabrics that work for beefier applications.

VX07 is actually a bit heavier at 4.9 ounces per sq yard. On a packbag this is a 2 -3 ounce difference usually.

Not all XPAC fabrics have the inner protection film. Some do, some don't. X33 for instance does not have it and really does not need it since it is 330D Cordura.

As far as feel , they both (Cuben Hybrid / XPAC) have a similar and sort of stiff feel initially. DP does have one fabric, that is lighter than the Cuben hybrid at 1.8 ounces, but IMO this is a good fabric for a true UL pack, that is constrained to someone operating and using with a bit of care.

I've used both the fabrics and personally would put VX07 and Cuben hybrid as about the same in regards to abrasion.

So why use heavier fabrics ? To extend the life of a product, through multiple users and adventures, and to reduce returns / defects when packs are used outside the realm of what the design / fabric is intended for. Yes, we can explain to someone the pack wasn't made for a certain type of use, but it easier to not have the conversation at all. We make our suspension components out of 500 D Cordura, simply because we don't want them to wear out for a long long time. Yes we have used pack cloths and they worked, but I prefer the longevity of Cordura. With the Paradox, / Seek Outside packs, we know where we have opportunities to save weight, but we view most of these opportunities as having too much of an impact on longevity. We can use lighter foam, lighter materials and have done a lot of testing with these, but we have greater piece of mind adding a couple ounces and using more substantial components at high stress areas.

In pure theoretical terms, and applying some usage limits, say confining to a more "ultralight with some care", we could get a Paradox / Seek Outside style design close to 2 lbs and still have a very good carry and fit to 60 and perhaps 80 lbs. We have not pursued this yet, because, at least for me it would not be a pack I could use for everything. Yes I would love a 35 ounce (as an example) pack that carried 60 lbs great, but there are times it would get stored in the closet as it would just not be suitable for the task. Also, I can get very close to 35 ounces now on the present design, by using the UL frame, a Cuben Base Talon, and a lightweight Cuben Roll Top Bag, or even Silnylon in more of a large "stuff sack" style.

Regarding The Arc Blast / Zpacks being a competitor, I would not consider that at all personally. The Arc BLast looks like a great pack, and innovative design but I would suspect the design goals are very different. The Arc Blast looks like a great UL pack, where the Paradox / Seek Outside is more of a platform.

Thanks so much for the info, Kevin. At least for my purposes, I prefer the heavier x-pac fabrics. Also to clarify, the DP fabric I was comparing to hybrid cuben was *t*x-07, not vx-07--I don't have any and was referring to specs from Rockywoods--they show it as 3.2 oz/sy and without the layer of scrim over the PET film, unlike the vx fabrics.

"I've used both the fabrics and personally would put VX07 and Cuben hybrid as about the same in regards to abrasion."

Interesting. VX-07 is an ideal trail fabric in my book. It seems to do ok with bushwacking, but not with hauling and rock bashing. TX-07 is good for extension collars only, though its transparency is kinda nifty.

The Cilo woven/non-woven dyneema is a pretty phenomenal fabric. Better abrasion resistance than 1000D cordura for less than half the weight, and waterproof to boot. For the price (~100 bucks a yard) it bloody well ought to be.

Cuben Hybrid also comes in a few face fabric options, which seems to be less well known.

It's been a while since I looked into it, but I think the Zpacks stuff (2.9oz/yd) uses a 30D face fabric polyester, while the stuff HMG and ULA use (~3.3oz/yd) uses a 50 or 70D face fabric, and then I think there's another option that's less well known but heavier still around 4-5oz/yd.

Dave's assessment is pretty much spot on in my book. VX07, is a great trail, or bushwhacking fabric, not great for things like rock bashing etc. IMO, the hybrid Cuben is about the same. Granted with some care, it is possible to mitigate some of the rock bashing , but it's not always feasible if your pack is on a haul loop for a 100 ft drop and it's windy and cliffy and it has 40 lbs in it.

Interestingly enough, I went on a recent canyon trip with a VX07, VX21, and Tan 210 D packs. I chose not to ask anyone to be careful and let kids be kids. The Tan 210D (3.9 ounce sq yard) faired the best, with only some minor abrasion on the bottle pockets. This was mostly due to the fact the person using the Tan just took a little more care and they had a bigger day talon (in VX33) which took most of the punishment.

While I haven't used any for a pack (but have played with samples), the heavier hybrids seem pretty promising (looks like cascade craftworks sells a 150d face version for MYOG). The hybrid face fabrics are impressively abrasion resistant for their weight because they're such a super tight weave. They're also impressively stiff, which I worried would cause some sharp corners that would be prone to wear, but depending on how much it breaks in this might not be a concern.

The full spectra/cuben laminates that Cilo/McHale uses is functionally about as perfect as you can ask. Cost, color, and the fact I have the itch to build a new pack and mine looks to be a couple decades from wearing out seem to be the only downsides. The DP DX40/D40 could be similar if they'd just put some spectra in both parts of the weave. It's as tough as anything in one direction and the other you can tear it easily with your hands.

The biggest thing to keep in mind with all of this is that every fabric has applications, and within the design of gear (especially backpacks), success is going to come from matching an appropriate fabric to a fitting design element.

When I consider fabrics for use in packs, I generally look at four things:

1.Relative tear strength- How easy will a fabric shred when it is pulled and tugged upon. This is mostly affecting stitch hole elongation, very important for load-bearing areas, (ie suspension-systems: shoulder strap and hipbelt attachment points)

2. Abrasion resistance- How will the fabric hold up to abrasion. These needs are dependant upon design elements. A 40denier or 70denier fabric may be appropriate for an extension collar, but I generally dont want the bottom or front of my pack made solely of this stuff (unless I'm going SUL!)

3. Waterproofness- How well will a fabric resist water penetration through the fabric. (PU coatings are generally more supple, but wear off in time. Laminates (like Xpac or cuben maintain their waterproofness longer (or so we're led to believe))

4. Long term durability- how well will a fabric hold up to UV degradation, will a PU(or other coating wear off with time, etc)

Other factors like stiffness, color etc are a bit less functionally important to me as a bag designer.

The three big players for pack fabrics right now seem to be Xpac(several styles), Cuben(two hybrid variants) and the ever popular 210 Dyneema Ripstop.

"So what advantage (if any) does hybrid cuben have over Dimension Polyant fabrics"

The tensile strength per weight is FAR higher. The dyneema content of cuben is the cause of this. Dyneema being a much stronger material than nylon or polyester PER WEIGHT

For regular non-woven cuben(rarely seen in heavy-use packs), sewing is an issue because of stitch-hole elongation. This comes from the VERY loose-knit structure of dyneema thread in the material(hold a piece of cuben up to light and you can see all the individual threads).

For Hybrid cubens, the face fabric helps solve the issue with stitch hole elongation(but then is only as effective as the face fabric plus the cuben, and the lighter weight hybrids have only a 50D face fabric).

Any Dimension Polyant Xpac fabric whos name begins with "V" as in VX70, VX21 etc has a LINER of 50d polyester. That has the same denier (thickness) as the FACE fabric of the common 'lightweight' hybrid Cuben.

IMHO, it's hard to find a true workhorse fabric under 4oz/yd2. I personally don't see the lightweight cuben hybrid as a workhorse fabric. It fills a niche and thats great. But as a general use pack fabric, its abrasion resistance is too low for my liking.

Looking to the future,a new fabric that I'm excited about, and have been testing and sewing with the last 6-8 months is the new Xpac X21. It consists of a 210D nylon face, Xpac grid and a thicker .5mil (instead of .25mil) film. No 50d Scrim. Lack of scrim (most likely a wash for a 210d Fabric) creates a fabric about 25% Lighter than the common VX21 While maintaining similar tear strength(at this denier of fabric, the tear strength comes mostly from the face fabric anyway).

DP seems to be creating this option for their larger Denier fabrics(as evidenced by the new X51 also, and the soon to be restocked X33). It makes a good deal of sense to me.

All said, I'm an Xpac man myself, but I see the viability of a niche for cuben hybrid. The DyneemaX stuff is great too, but from a producers perspective, Xpac is a better value, delivering much more bang for the buck.

Kevin said:

"Not all XPAC fabrics have the inner protection film. Some do, some don't. X33 for instance does not have it and really does not need it since it is 330D Cordura."

To clarify, Kevin, I assume you're referring to the 50d polyester liner 'Scrim', not the film. I have never seen an Xpac fabric that does not have a waterproof PET(or otherwise) film.

Brendan says:"The DP DX40/D40 could be similar if they'd just put some spectra in both parts of the weave. It's as tough as anything in one direction and the other you can tear it easily with your hands."

I'm sitting here with a piece of D40 trying my best to tear it in either direction, and it wont budge. Perhaps I'm just weak, but it wont tear easily in either direction for me. If I remember correctly, it's a 400D polyester warp/400D spectra weft plus a 600D Spectra ripstop face fabric on, a .25mil PET film and 50D polyester liner/scrim. In my little experience, that would add up to TOUGH AS NAILS. I was told DP uses polyester in the face fabric so that their laminate will stick to the fabric better.

Reminiscing, many Years ago There was a pack maker (I believe SMD) that offered a 210D Dyneema ripstop that was produced by Xpac. It was an amazing fabric. The strength of the workhorse 210D Dyneema ripstop with the waterproofness of xpac laminates (and a 50d Polyester scrim) I made my my fifth backpack out of this stuff and it lasted me nearly 7 years of hard use. Eventually the scrim fabric delaminated from the face fabric and I cannibalized it. If I had the capital to purchase 1000 yards of uncoated dyneema ripstop and have Xpac laminate it for me, I'd be all over it.

P.S.

For fun, as a very unscientific test of abrasion resistance you can do at home: scrape a rough rock across the face of a fabric it until you put a hole in it. Try with 50Denier, 70 Denier 150 Denier 210Denier fabrics etc. You will get a general idea of relative abrasion resistance. Cuben(sub 2oz) without a face fabric SHREDS NEARLY RIGHT AWAY(as does silnylon, TX34 etc)

As far as I'm concerned, the hybrid cubens are only slightly more abrasion resistant than their face fabric.The Cuben laminate itself doesn't add much. For a 150D fabric, that adds up to maybe as resistant as a 210D fabric, but the Cuben laminate itself, a 9k (heavyweight) version in the 150d hybrid adds a huge margin to tear and tensile strength, blowing traditional 210d wovens away.

All speculation here as I don't have any data to back it up.(aside from manufacturer specs on Xpac and Cuben)

That being said, it is heavier than x21 and DyneemaX, but lighter than vx21.

P.s. Anyone with the money to buy minimums could have Cubic Tech custom produce a fabric with varying properties by combining face fabrics and laminates. Just like Dimension Polyant produces nearly 800 custom fabrics a year(or so I'm told).

Re: The Grocery Sack Grows Up: A Genealogy of the Modern Ultralight Backpack
on 04/09/2014 21:27:13 MDT

Dave C said,

"Beyond RayWay the trail gets very diffuse, and the print evidence even thinner. That '82 Backpacker article is about the only thing I could dig up from that decade. It would be great to tell the tale of how those products lost favor, but I couldn't get enough sources. It doesn't help that my own recollection of gear trends begin in the early 90s."

------------------------------------------

Tony has really helped fill in some of the blanks. For all things backpacking in the U.S. in the past 50+ years, it seems the trail constantly crosses the path of Colin Fletcher, which I will explain.

In 1959 he published the 1,000 Mile Summer, a book that slowly gained popularity over the years. A few years after the book was published, the 60's Counter-culture Revolution and a quasi back-to-nature movement saw backpacking gain popularity. Then in 1968 Fletcher published the first Complete Walker book, which (with subsequent revised editions) influenced most modern backpackers directly or indirectly.

Then in the early 70's we see a covey of frameless packs hit the market, all under 3 lbs and some close to 2 lbs. The 3 most popular brands were owned or influenced by Don Wittenberger, whose designs morphed the alpine rucksack into a larger frameless packs suitable for backpacking. The 3 packs were the Rivendell Jensen, Yakworks Yakpak, and the Pacific Ironworks (Chouinard) Ultimate Thule. Now 2-3 lbs may seem heavy, but keep in mind that materials were limited and these packs were built by climbers with an eye towards durability. I remember seeing ads for all 3 packs and availability in mail order catalogs. I never owned any of them, but saw a few in the backcountry. I seem to remember some of them even had "load lifters."

Like we are seeing today, with a decline in frameless packs and movement to UL framed-packs, a lot of people modified these Wittenberger packs by adding internal stays or other kinds of suspension upgrades. The biggest problem for these 3 early companies was the lack of an economical method to market to the mainstream backpacker -- there was no Internet and they could not produce the quantities needed to attract a mainstream retailer.

So what killed these 3 packs for backpacking? Two things:

The first was that without a frame they didn't do the job for long trips, and it seems that people did more longer trips back then, than today -- that is -- not a lot of overnighters or short trips like a lot of people do today; but more trips in the 5 - 7 day range. A we certainly weren't doing boutique hiking by dropping into a trail town every 3-5 days on our big long hikes of several weeks or several months.

The 2nd thing that killed the Jensen and it's brethren was Fletcher's Complete Walker II (1974), a book that really started driving the popularity of backpacking and the sales of external frame packs, which became easily available from the large mail order companies like REI and large retailers. If Fletcher used an external, then that is what you should buy.

Now we head into the early 80's with the AlpenLITE and many other similar light packs. Along with this next generation/iteration of frameless packs, articles are written about lightweight backpacking, and many people start hiking with lighter gear, but it was still a niche just as it is today. Many people "embraced" lightness, myself included, and lots of us continued to do so over the decades.

Things have gotten lighter over the years mostly due to the innovation in materials, not design.

Tony mentioned Kennedy and Williams. It is also interesting that in The Complete Walker III (1984), Fletcher also mentions them, calling it the New Wave. Fletcher doesn't necessarily endorse it, he calls it evolution, casts a hopeful eye to what may be possible, and reiterates that New Wave Lightness Skills are needed... he uses the metaphor of an Indy race car driver versus the normal person driving a Chevy.

What Fletcher does do in this 3rd edition is kill the external frame pack and the second generation of (1980's) commercial frameless packs.

He also killed Gregory's super light packs, which Wayne Gregory knows is the reason they didn't sell.

How did Fletcher do this?

Well after 26 years of the Fletcher minions emulating him with their external frame packs (Fletcher had a Trailwise, but Kelty had the market share), Fletcher drops a bombshell by abandoning his external and extolling the virtues of the Gregory Cassin -- a really heavy internal frame pack. Cassin sales go through the roof, Gregory gets rich and owes his success to Fletcher, sales of internal packs by all the other brands go crazy, and the externals & frameless packs die. No one holds a funeral because the internals are more expensive and retailers hold good gross on sales.

But some folks didn't go the Fletcher Way, especially for shorter trips. In the backcountry there was a minority with rucksacks, or even those who just removed their internal frames. Instead, I kept my light external and reduced the weight of everything I carried in it.

So, there isn't a Ray Way -- it exists only in Jardine's mind.

Yes, he help popularize this next iteration of lightweight backpacking, but he surely didn't invent it or the Stuff Sack with Straps. The Internet popularized the "new" fad. Ray happened to publish at the beginning of the Internet age. To be honest, Ryan Jordan probably has had the biggest impact popularizing lightweight backpacking by starting BPL.